YUV planes cache

- Added new classes to contain YUV planes of memory, along with the associated data.
- Used these classes in load_yuv_texture() to enable YUV planes caching
- Added a unit test for the new cache

BUG=450021

Review URL: https://codereview.chromium.org/851273003

1 files changed, 83 insertions, 0 deletions

diff --git a/src/core/SkYUVPlanesCache.cpp b/src/core/SkYUVPlanesCache.cpp
new file mode 100644
index 0000000000..69885fe46a
--- /dev/null
+++ b/src/core/SkYUVPlanesCache.cpp
@@ -0,0 +1,83 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkYUVPlanesCache.h"
+#include "SkResourceCache.h"
+
+#define CHECK_LOCAL(localCache, localName, globalName, ...) \
+    ((localCache) ? localCache->localName(__VA_ARGS__) : SkResourceCache::globalName(__VA_ARGS__))
+
+namespace {
+static unsigned gYUVPlanesKeyNamespaceLabel;
+
+struct YUVValue {
+    SkYUVPlanesCache::Info fInfo;
+    SkCachedData*          fData;
+};
+
+struct YUVPlanesKey : public SkResourceCache::Key {
+    YUVPlanesKey(uint32_t genID)
+        : fGenID(genID)
+    {
+        this->init(&gYUVPlanesKeyNamespaceLabel, sizeof(genID));
+    }
+
+    uint32_t fGenID;
+};
+
+struct YUVPlanesRec : public SkResourceCache::Rec {
+    YUVPlanesRec(YUVPlanesKey key, SkCachedData* data, SkYUVPlanesCache::Info* info)
+        : fKey(key)
+    {
+        fValue.fData = data;
+        fValue.fInfo = *info;
+        fValue.fData->attachToCacheAndRef();
+    }
+    ~YUVPlanesRec() {
+        fValue.fData->detachFromCacheAndUnref();
+    }
+
+    YUVPlanesKey  fKey;
+    YUVValue      fValue;
+
+    const Key& getKey() const SK_OVERRIDE { return fKey; }
+    size_t bytesUsed() const SK_OVERRIDE { return sizeof(*this) + fValue.fData->size(); }
+
+    static bool Visitor(const SkResourceCache::Rec& baseRec, void* contextData) {
+        const YUVPlanesRec& rec = static_cast<const YUVPlanesRec&>(baseRec);
+        YUVValue* result = static_cast<YUVValue*>(contextData);
+
+        SkCachedData* tmpData = rec.fValue.fData;
+        tmpData->ref();
+        if (NULL == tmpData->data()) {
+            tmpData->unref();
+            return false;
+        }
+        result->fData = tmpData;
+        result->fInfo = rec.fValue.fInfo;
+        return true;
+    }
+};
+} // namespace
+
+SkCachedData* SkYUVPlanesCache::FindAndRef(uint32_t genID, Info* info,
+                                           SkResourceCache* localCache) {
+    YUVValue result;
+    YUVPlanesKey key(genID);
+    if (!CHECK_LOCAL(localCache, find, Find, key, YUVPlanesRec::Visitor, &result)) {
+        return NULL;
+    }
+    
+    *info = result.fInfo;
+    return result.fData;
+}
+
+void SkYUVPlanesCache::Add(uint32_t genID, SkCachedData* data, Info* info,
+                           SkResourceCache* localCache) {
+    YUVPlanesKey key(genID);
+    return CHECK_LOCAL(localCache, add, Add, SkNEW_ARGS(YUVPlanesRec, (key, data, info)));
+}